Ah, I see the disconnect. You're talking about 50-50 cards instead of clans and treating +pill as an ability. Having 1 or 2 pill manip cards in your deck is totally fine and not 50-50ish at all. Heck, I've used grudg to get to 1400 elo before and I'm a huge fan of tremorh. A timely pill manip played in the third round is a great way to *prevent* 3rd/4th round 50-50s.

However, having an entire deck made up of pill manip cards is *very* chancey.. Instead of facing an opponent with tremorh, you're facing a opponent with a hand of Tremorh Taham Nobrodroid and Gil. There's a very good chance your game will devolve into a 50-50. A pill manip card or two in a deck is fine. Making a clan full of them can very well lead to unnecessarily chancey situations. It's like the difference between putting Jean in your deck and playing mono GHEIST

I feel like it all comes down to good old-fashioned math... Let's imagine that abilities and bonuses (or is it boni?) are interchangeable. For our purposes, I think they are. Now let's go through your example.

The hand you're suggesting is definitely a bit scary under the right conditions. A 3-round win is possible against many hands, and an early Gil win or something like that does set up a 50/50 situation (if you don't block the next pill manip guy, and you're probably going to lose.) But here are some important differences between that hand and the proposed clan:

1) There's a lot more pill manip than 2 per card. Gil has 3 and Nobrodroid has 4.
2) Because of the Junkz bonus, all of these cards have attack manip built in. That is important because it makes 3-rounding with this hand much easier. What are the odds that, when playing mono Theoretical Clan, I will draw a hand full of 8 attack manip on ability?

This is why #2 is really important... Imagine that I attack you with a 2-pilled Gil. Now imagine that because you are pretty sure he's a 1-pill bluff, you just 3-pill a 7 power with, say, a damage bonus. Gil still wins, resulting in a net loss of not 3 but 4 pills. See how the attack manip functions there?

If you can imagine a hand where everybody has +2 pills, and diverse abilities instead of all +8 attack, you will probably find that it is much less likely to create a 50/50 3 round situation.